70S2HA (EI142)

Springs of clock mechanisms, large springs for important purposes.

Classification

Country Section Category
CIS, Russia, Ukraine Structural steel Spring-spring structural steel

Chemical composition

Standard Fe, % Si, % Mn, % Cr, % Cu, % Ni, % P, % C, % S, %
GOST 14959-79 96.05–97.35 1.4–1.7 0.4–0.6 0.2–0.4 < 0.2 < 0.25 < 0.025 0.65–0.75 < 0.025

Information on suppliers

Mechanical properties at 20 °C

Rolling Standard Size, mm Tension Classifiers \sigma _{U}, MPa d5, % Treatment
The tape is annealed. GOST 2283-79 0.1–4 annealing 880 8
The tape is hardcore. GOST 2283-79 0.1–4 cold-work 780–1180

Technological Properties

Weldability Flake Susceptibility Propensity to temper brittleness
Not applicable for welded structures not sensitive not inclined

Analogues

Germany Bulgaria
1.5029 (71Si7) 70S2ChA

Standards

Standard Description
GOST 14959-79
GOST 2283-79 GOST 2283-79

Description of chemical elements

Element Units of measurement Description
Fe % Iron
Si % Silicon
Mn % Manganese
Cr % Chrome
Cu % Copper
Ni % Nickel
P % Phosphorus
C % Carbon
S % Sulfur

Description of mechanical properties

Parameter Units of measurement Description
d5 % Elongation at break
\sigma _{U} MPa Ultimate tensile strength

Designation of types of weldability

Parameter Units of measurement Description
no limits Welding is performed without heating and without subsequent heat treatment
Boundedly welded Welding is possible with heating up to 100–120 °C and subsequent heat treatment
Difficult to weld For obtaining quality welded joints, additional operations are required: heating up to 200–300 °C for welding, heat treatment after welding — annealing
Not applicable for welded structures